THE ST. LAWRENCE RIVER (in French, “fleuve Saint-Laurent”) was formed at the end of the last ice age. It is a 1,900-mile (3,058-kilometer) west-to-east, middle latitude river connecting the 5 Great Lakes with the . The French called the river Rivière du Canada until the early 1600s, but fleuve connotes a river that runs to the sea, a more appropriate designation. Called Kaniatarowanenneh (Big Waterway) in the Mohawk dialect of the Iroquoian language, the river forms a portion of the border between State and the province of Ontario, , and bisects the province of Quebec.
The river is the outlet for the Great Lakes (the Inland Seas), the 5 connected freshwater lakes in east central North America that straddle the international border between Canada and the United States. Collectively, these constitute the world’s largest body of fresh water, with a water surface of 94,000 square mile (244,000 square kilometer) and 5,500 cubic mile (23,000 cubic kilometer) of water. From west to east, the lakes are , , , (the shallowest), and . Together, they extend about 850 mile (1,370 kilometer) west to east and 700 mile (1,125 kilometer) from north to south.
The St. Lawrence begins at the outflow of Lake Ontario at Kingston, Ontario, passing Montreal and Quebec City before draining into the Gulf of St. Lawrence, the world’s largest estuary. The major islands include the Thousand Islands near Kingston; the Île de Montreal; Île Jésus (Laval); Île d’Orléans, near Quebec City; and Anticosti Island north of the Gaspé Peninsula. Lake Champlain and the Ottawa, Richelieu, and Saguenay rivers drain into the St. Lawrence. The river widens to approximately 61 mile (100 kilometer) beyond Quebec City.
The St. Lawrence begins at the outflow of Lake Ontario at Kingston, Ontario, passing Montreal and Quebec City before draining into the Gulf of St. Lawrence, the world’s largest estuary.
Ancient inhabitants occupied the river area for at least 5,000 years and Algonquin and Iroquois tribes inhabited the river basin and adjacent uplands prior to European contact. On June 9, 1534, Jacques Cartier first sighted the river and claimed the region for Francis I. The completion of the 9.1-mile (14.5-kilometer) Lachine Canal in 1825 allowed shipping to pass the rapids and navigate Lake Ontario.
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R. Cole Harris, ed., Historical Atlas of Canada, Vol. 1: From the Beginning to 1800 (University of Toronto Press, 1987); Theo Hills, The St. Lawrence Seaway (Praeger, 1959); William Toye, The St. Lawrence (Walck, 1959).
CHARLES C. KOLB
NATIONAL ENDOWMENT FOR THE HUMANITIES